Electronic apparatuses mounted on bicycles, for example, for controlling the electronic gearshift and/or for acquiring, displaying, and controlling riding parameters and various functions, provide for the use of a power supply unit.
The power supply unit typically consists of one or more batteries, typically connected in series, also referred to as a battery pack. The batteries used for such electronic devices are typically of the rechargeable type.
In the known apparatuses, in order to recharge the power supply unit without removing it from the electronic apparatus, a recharging device or battery charger is used which provides electrical energy from an external energy source, such as, for example, a conventional electrical outlet, in parallel to the power supply unit and to the electrical and electronic components of an electronic device intended, for example, for controlling and actuating an electronic gearshift and/or for acquiring, displaying, and controlling bicycle riding parameters and other functions, including interfacing with the cyclist.
The current supplied by the battery charger is therefore the sum of the recharge current which supplies the rechargeable battery power supply unit and the current which supplies the electronic device.
Consequently, it is not possible to effectively monitor the recharge current intensity supplied to the battery power supply unit, for example, in order to carry out the recharging through two controlled steps, i.e., an initial constant current step and a final constant voltage step.
The technical problem at the basis of the present invention is to allow an effective control of the recharge voltage and current in order to allow an optimal recharging of the battery power supply unit.